<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    div span {
      width: 100px;
      height: 20px;
    }

    div:not(span) {
      background: red;
    }

    div h1 {
      width: 100px;
      height: 20px;
    }

    div span {
      width: 100px;
      height: 20px;
    }

    div h2 {
      width: 100px;
      height: 20px;
    }
  </style>
</head>

<body>
  <div>
    <h1></h1>
    <span></span>
    <h2></h2>
  </div>
</body>

</html>